Golf club head

ABSTRACT

A golf club head includes a front face having a grooved striking zone for impacting a golf ball, a rear face opposite to said front face, a top portion, a sole portion, a toe portion, a heel portion, a hosel portion having a shaft-receiving bore. The toe portion surface meets the front face along a first edge, and the toe portion extends outwardly from the first edge in a direction away from the hosel portion such that the vertical projection of the toe portion onto a plane containing the front face is substantially located outside of the front face. Besides, the sole surface meets the rear face along a trailing edge and meets the toe portion surface along a second edge, and the angle included between the trailing edge and the second edge is less than 90 degrees.

BACKGROUND

1. Field of Invention

The present invention relates to a golf club head with a high moment ofinertia.

2. Description of Related Art

Two important factors involved for resulting in an ideal impacting of agolf ball are, first, that the impact point on the front face of thegolf club head should ideally be in alignment with the center of gravityof the golf club head and with the center of gravity of the golf ball;secondly, that the front face of the golf club head should be squarewith the intended travel path of the golf ball. At the time of impact,deviations from the ideal alignment of the impact point on the frontface of the golf club head, the center of gravity of the golf club headand the center of gravity of the golf ball will result in less than amaximum transfer of energy, that is to say, the travel length of thegolf ball is shortened. At the time of impact, if the front face of thegolf club head is not perpendicular to the intended travel path of thegolf ball, the golf ball will deviate from the intended travel path.

Referring to FIG. 4, if the impact point 402 on the front face 408 ofthe golf club head is laterally offset toward the toe of the golf clubhead such that the ideal alignment of the impact point 402 on the frontface 408 of the golf club head, the center of gravity 404 of the golfclub head and the center of gravity 406 of the golf ball is notachieved, the offset of the impact point 402 will cause the golf clubhead to rotate at the time of impact about an axis which passes throughthe center of gravity of the golf club head besides shortening thetravel length of the golf ball such that a impact accuracy is affected.

It will be appreciated that it can be very difficult even forexperienced golfers to achieve the ideal impacting of a golf ball.Therefore, it is needed to provide a new golf club head for reducing thegyrations caused by the offset of the impact point.

SUMMARY

It is an object of the present invention to provide a golf club headwith high moments of inertia for providing better gyration dampeningcharacteristics to reduce the gyrations caused by the offset of theimpact point.

To achieve the above listed and other objects, a golf club headaccording to one embodiment of the present invention includes a frontface having a grooved striking zone for impacting a golf ball, a rearface opposite to said front face, a top portion, a sole portion, a toeportion, a heel portion, and a hosel portion having a shaft-receivingbore. The toe portion surface meets the front face along a first edge,and the toe portion extends outwardly from the first edge in a directionaway from the hosel portion such that the vertical projection of the toeportion onto a plane containing the front face is substantially locatedoutside of the front face. Besides, the sole surface meets the rear facealong a trailing edge and meets the toe portion surface along a secondedge, and the angle included between the trailing edge and the secondedge is less than 90 degrees.

According to another embodiment of the present invention, there isprovided an iron type golf club head including a front face having agrooved striking zone for impacting a golf ball, a rear face opposite tosaid front face, a top portion, a sole portion, a toe portion, a heelportion, and a hosel portion having a shaft-receiving bore. The toeportion surface meets the front face along a first edge, and the toeportion extends outwardly from the first edge in a direction away fromthe hosel portion such that the vertical projection of the toe portiononto a plane containing the front face is substantially located outsideof the front face. Besides, the sole surface meets the rear face along atrailing edge and meets the toe portion surface along a second edge, andthe angle included between the trailing edge and a tangent line drawntangent to the toe portion at the outmost point of the toe portion asviewed in a top view is less than 90 degrees.

According to another embodiment of the present invention, there isprovided an iron type golf club head including a front face having agrooved striking zone for impacting a golf ball, a rear face opposite tosaid front face, a top portion, a sole portion, a toe portion, a heelportion, and a hosel portion having a shaft-receiving bore. The toeportion surface meets the front face along a first edge, and the toeportion extends outwardly from the first edge in a direction away fromthe hosel portion such that the vertical projection of the toe portiononto a plane containing the front face is substantially located outsideof the front face. Besides, the sole surface meets the rear face along atrailing edge and at least a central portion of the trailing edge isindented toward the front face.

The present invention has the advantage of improving the impact accuracyof the golfers at the time of impact to raise the scores andcompetitiveness of the golfers in races.

BRIEF DESCRIPTION OF THE DRAWINGS

Aspects of the present disclosure are best understood from the followingdetailed description when read with the accompanying figures. It isemphasized that, in accordance with the standard practice in theindustry, various features are not drawn to scale. In fact, thedimensions of the various features may be arbitrarily increased orreduced for clarity of discussion. In the accompanying figures:

FIG. 1A is a front view of a golf club head according to one embodimentof the present invention;

FIG. 1B is a bottom view of the golf club head of FIG. 1A;

FIG. 1C is a top view of the golf club head of FIG. 1A;

FIG. 1D is a side view of the golf club head of FIG. 1A;

FIG. 2 is a top view of a golf club head according to another embodimentof the present invention;

FIG. 3A is a front view of a golf club head according to anotherembodiment of the present invention;

FIG. 3B is a bottom view of the golf club head of FIG. 3A;

FIG. 3C is a top view of the golf club head of FIG. 3A;

FIG. 3D is a top view of the golf club head of FIG. 3A; and

FIG. 4 is a front view of the relative positions between a golf clubhead and a golf ball at the time of impact.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

While the present invention is susceptible of embodiment in variousforms, there are presently preferred embodiments shown in the drawingsand will hereinafter be described with the understanding that thepresent disclosure is to be considered as an exemplification of theinvention and is not intended to limit the invention to the specificembodiment illustrated.

Referring to FIG. 1A to 1D, which show a golf club head 100 according toone embodiment of the present invention. The golf club head 100 is ahollow club head including a front face 102, a rear face 104 opposite tothe front face 102 (see FIG. 1C), a top portion 112 forming an upperpart of the golf club head (see FIG. 1C), a sole portion 114 forming alower part of the golf club head (see FIG. 1B), a toe portion 108, aheel portion 106, a hosel portion 120 having a shaft-receiving bore 120a, wherein the front face 102 has a grooved striking zone 102 a forimpacting a golf ball (see FIG. 1A) and a plurality of score lines 102 bextending horizontally on the grooved striking zone 102 a in a directionsubstantially parallel to sole portion 114.

A golf club head is generally composed of two components, a faceplate,and a main body. The aforementioned grooved striking zone 102 a isdisposed on the faceplate surface which constitutes one part of thefront face 102. The faceplate could be composed of a forged metal (e.g.,Cp-Ti, 6-4 titanium alloy, titanium 15-3-3-3 alloy, and pure titanium).In certain embodiments, metals for the faceplate include stainlesssteel, carbon steel, aluminum alloy, other high strength steel alloymetals and amorphous metals. The main body includes the aforementionedportions of golf club head except the faceplate, and the main body couldbe composed of metals such as carbon steel (e.g. carbon steelcorresponding to JIS S20C or S25C), stainless steel (e.g. 17-4PHstainless steel), alloy steel, Fe—Mn—Al alloy, nickel based alloys, castiron, super alloy steel, pure titanium, titanium alloy (e.g. 6-4titanium alloy or Cp-Ti), aluminum alloy, magnesium alloy, or copperalloy. The aforementioned faceplate and main body could be integrallyformed as one unit. Alternatively, the golf club head of the presentinvention may be manufactured by integrally casting a main body having afaceplate-fitting opening by a lost wax method, fitting a faceplate inthe opening, and welding the faceplate to the main body. If a weldingprocess is conducted, the welded product may be further subjected togrinding or age hardening. Furthermore, the aforementioned faceplate andmain body could be manufactured through casting, forging, forming,machining, powdered metal forming, metal-injection-molding, electrochemical milling, and the like.

It is noted that the toe portion 108 surface of the golf club head 100meets the front face 102 along a edge 110 (see FIG. 1A), and the toeportion 108 extends outwardly from the edge 100 in a direction away fromthe hosel portion 120 such that the vertical projection of the toeportion 108 onto a plane containing the front face 102 is substantiallylocated outside of the front face 102. In FIG. 1C, dash lines illustratethe outline of a conventional golf club head, wherein the verticalprojection of its toe portion onto a plane containing its front face islocated completely inside of its front face. One purpose of the presentinvention is to redistribute materials within the dash lines to the toeportion 108 for increasing the club head's moment of inertia. Besides,the surface of the sole portion 114 of the golf club head 100 meets therear face 104 along a trailing edge 116 (see FIGS. 1B and 1C), and meetsthe surface of the toe portion 108 along a edge 118, wherein the angleθ1 (see FIG. 1B) included between the trailing edge 116 and the edge 118is designed to be less than 90 degrees. In certain embodiments, theangleθ 1 (see FIG. 1B) between the trailing edge 116 and the edge 118 isdesigned to be between 30 degree and 90 degree. Such designs allowmaterials of the golf club head to be redistributed to the toe portion108.

The golf club heads having features of the present invention have amoment of inertia ranging from 3000 grams-centimeters squared to 6000grams-centimeters squared, wherein the moment of inertia is definedabout a vertical axis L (see FIG. 1A) passing through the center ofgravity CG of the golf club head 100 and perpendicular to a ground G(see FIG. 1A) upon which the golf club head 100 rests. According to thedefinition of the moment of inertia, I=∫r²dm, a distance r between adifferential mass dm of the golf club head 100 and a rotation axis hasmore influence on computing the moment of inertia than the differentialmass dm, so the present invention's design could effectively increasethe club head's moment of inertia about the vertical axis L.

The moment of inertia of the golf club head 100 is a design propertythat has a bearing on the amount of “forgiveness” that a club headoffers for mis-hits. The larger the golf club head 100, and/or the morethe designer incorporates perimeter weighting, the higher the moment ofinertia of the golf club head 100 about its vertical axis L passingthrough the center of gravity CG will be. The higher the moment ofinertia of the golf club head 100 about its vertical axis L, the lessthe golf club head 100 will twist in response to a mis-hit, and the lessdistance will be lost from that mis-hit. For this reason, the impactaccuracy, which may be adversely affected by misalignment of the impactpoint on the front face 102 of the golf club head 100 with the center ofgravity CG of the golf club head 100 and the center of gravity of a golfball, could be improved as the moment of inertia of the golf club head100 increases.

In certain embodiments, the trailing edge 116 of the golf club head 100has a central portion indented toward the front face 102 such that moreweight of the golf club head 100 could be distributed to the toe portion108 or the heel portion 106 thereby further increasing the moment ofinertia of the golf club head 100. In certain embodiments, the centralportion of the trailing edge 116 of the golf club head 100 is ofarcuately extending configuration, but not intended to limit theinvention to this specific embodiment illustrated, for example, that thecentral portion of the trailing edge 116 may be of substantiallylinearly extending configuration.

Referring to FIG. 2, in certain embodiments, in order to furtherincrease moment of inertia of the golf club head 200, the rear face 104a of the head 200 may be provided with a cavity 104 b indented towardthe front face 102 for distributing more materials to the toe portion108 or the heel portion 106 of the golf club head 200.

In certain embodiments, the angleθ 2 included between the trailing edge116 of the golf club head 100 and a tangent line 122 (see FIG. 1C) maybe designed to be less than 90 degrees, wherein the tangent line 122 isdrawn tangent to the toe portion 108 at the outmost point A of the toeportion 108 as viewed in a top view. In certain embodiments, the angleθ2 (see FIG. 1C) between the trailing edge 116 and the tangent line 122may be designed to be between 30 degree and 90 degree.

The impact accuracy problem caused by the impact point offset could beimproved when the angleθ 1 and/or the angleθ 2 is designed to be lessthan 90 degree for increasing the moment of inertia of the golf clubhead 100.

In certain embodiments, the distance AB between a point A (see FIG. 1A),which is the outmost point of the toe portion 108 as viewed in a frontview, and a point B (see FIG. 1A), which is the outermost point of theedge 110 as viewed in a front view, is at least 4 mm.

When the sole 114 of the golf club head 100 rests on the ground G asshown in FIG. 1A, the distance CD between a point C and a point D issubstantially larger than a distance DE between the point D and a pointE, wherein the point C represents a vertical projection point on theaforementioned ground G of the outmost point A of the toe portion 108 asviewed in a front view, the point D represents a projection point on theground G of the central axis of the shaft-receiving bore 120 a of thehosel portion 120, and the point E represents a vertical projectionpoint on the ground G of the outermost point of the edge 110 as viewedin a front view. In certain embodiments, the distance CD is larger thanthe distance DE by at least 4 mm.

Referring to FIGS. 3A, 3B and 3C, which show a golf club head 300according to another embodiment of the present invention, the golf clubhead 300 is a iron type club head including a front face 102, a rearface 104 c opposite to the front face 102 (see FIG. 3C), a top portion112 (see FIG. 3C), a sole portion 114 a (see FIG. 3B), a toe portion108, a heel portion 106, a hosel portion 120 having a shaft-receivingbore 120 a, wherein the front face 102 has a grooved striking zone 102 afor impacting a golf ball and a plurality of score lines 102 b extendinghorizontally on the grooved striking zone 102 a in a directionsubstantially parallel to sole portion 114 a.

In this embodiment, the surface of the toe portion 108 of the golf clubhead 300 meets the front face 102 along a edge 110 (see FIG. 3A), andthe toe portion 108 extends outwardly from the edge 100 in a directionaway from the hosel portion 120 such that the vertical projection of thetoe portion 108 onto a plane containing the front face 102 issubstantially located outside of the front face 102. Referring to FIG.3D, dash lines are used to illustrate the outline of a conventional golfclub head, wherein the projection of its toe portion onto a planecontaining its front face is located completely inside of its frontface. One purpose of the present invention is to redistribute materialswithin the dash lines to the toe portion 108 for increasing the momentof inertia of the golf club head. Besides, the surface of the soleportion 114 a of the golf club head 300 meets the rear face 104 c alonga trailing edge 116 a (see FIGS. 3B and 3C), and the trailing edge 116 aincludes at least a central portion indented toward the front face 102(see FIGS. 3B and 3C). This design also can increase the moment ofinertia of the golf club head for improving the impact accuracy problemcaused by the impact point offset.

In this embodiment, the central portion of the trailing edge 116 a is ofarcuately extending configuration. Alternatively, the central portion ofthe trailing edge 116 a may be of substantially linearly extendingconfiguration. The golf club head 300 of this embodiment has a moment ofinertia ranging from 3000 grams-centimeters squared to 6000grams-centimeters squared, wherein the moment of inertia is calculatedin the same manner as above. In certain embodiments, a rear face 104 cof the golf club head 300 may include a cavity 104 d indented toward thefront face 102 to distribute more materials to the toe portion 108.

In certain embodiments as shown in FIG. 3A, the distance AB between apoint A and a point B is at least 4 mm, and the distance CD issubstantially larger than a distance DE when the sole 114 a rests on theground G (see FIG. 3A), wherein the definition of correlated points anddistances thereof is the same as the definition aforementioned in theembodiments shown in FIG. 1A, so that there is no more descriptionagain.

The foregoing has outlined features of several embodiments so that thoseskilled in the art may better understand the detailed description thatfollows. Those skilled in the art should appreciate that they mayreadily use the present disclosure as a basis for designing or modifyingother processes and structures for carrying out the same purposes and/orachieving the same advantages of the embodiments introduced herein.Those skilled in the art should also realize that such equivalentconstructions do not depart from the spirit and scope of the presentdisclosure, and that they may make various changes, substitutions andalterations herein without departing from the spirit and scope of thepresent disclosure.

1. A golf club head comprising: a front face having a grooved strikingzone for impacting a golf ball; a rear face opposite to said front face;a top portion; a sole portion; a toe portion; a heel portion; and ahosel portion having a shaft-receiving bore, wherein the toe portionsurface meets said front face along a first edge, and said toe portionextends outwardly from said first edge in a direction away from saidhosel portion such that the vertical projection of said toe portion ontoa plane containing said front face is substantially located outside ofsaid front face, wherein the sole surface meets said rear face along atrailing edge and meets said toe portion surface along a second edge,and the angle included between said trailing edge and said second edgeis less than 90 degrees.
 2. The golf club head of claim 1, wherein theangle included between said trailing edge and said second edge isbetween 30 and 90 degrees.
 3. The golf club head of claim 1, whereinsaid trailing edge has a central portion indented toward said frontface.
 4. The golf club head of claim 1, wherein the golf club head has amoment of inertia about a vertical axis between 3000 grams-centimeterssquared and 6000 grams-centimeters squared, and said vertical axispasses through the center of gravity of the golf club head and saidvertical axis is perpendicular to a ground the golf club head rests on.5. The golf club head of claim 1, wherein the distance AB between apoint A, which is the outmost point of said toe portion as viewed in afront view, and a point B, which is the outermost point of said firstedge as viewed in a front view, is at least 4 mm.
 6. The golf club headof claim 1, wherein when said sole rests on a ground, a distance ABbetween a point A, which is a vertical projection point on said groundof the outmost point of said toe portion as viewed in a front view, anda point B, which is a projection point on the ground of the central axisof said shaft-receiving bore, is substantially larger than a distance BCbetween said point B and a point C, which is a vertical projection pointon the ground of the outermost point of said first edge as viewed in afront view.
 7. The golf club head of claim 1, wherein said rear face hasa cavity indented toward said front face.
 8. An iron type golf club headcomprising: a front face having a grooved striking zone for impacting agolf ball; a rear face opposite to said front face; a top portion; asole portion; a toe portion; a heel portion; and a hosel portion havinga shaft-receiving bore; wherein the toe portion surface meets said frontface along a first edge and said toe portion extends outwardly from saidfirst edge in a direction away from said hosel portion such that thevertical projection of said toe portion onto a plane containing saidfront face is substantially located outside of said front face; whereinthe sole surface meets said rear face along a trailing edge and theangle included between said trailing edge and a tangent line drawntangent to said toe portion at the outmost point of said toe portion asviewed in a top view is less than 90 degrees.
 9. The iron type golf clubhead of claim 8, wherein the angle included between said trailing edgeand said tangent line is between 30 and 90 degrees.
 10. The iron typegolf club head of claim 8, wherein said trailing edge has a centralportion indented toward said front face.
 11. The iron type golf clubhead of claim 8, wherein the iron type golf club head has a moment ofinertia about a vertical axis between 3000 grams-centimeters squared and6000 grams-centimeters squared, and said vertical axis passes throughthe center of gravity of the iron type golf club head and said verticalaxis is perpendicular to a ground the iron type golf club head rests on.12. The iron type golf club head of claim 8, wherein the distance ABbetween a point A, which is the outmost point of said toe portion asviewed in a front view, and a point B, which is the outermost point ofsaid first edge as viewed in a front view, is at least 4 mm.
 13. Theiron type golf club head of claim 8, wherein when said sole rests on aground, a distance AB between a point A, which is a vertical projectionpoint on said ground of the outmost point of said toe portion as viewedin a front view, and a point B, which is a projection point on theground of the central axis of said shaft-receiving bore, issubstantially larger than a distance BC between said point B and a pointC, which is a vertical projection point on the ground of the outermostpoint of said first edge as viewed in a front view.
 14. The iron typegolf club head of claim 8, wherein said rear face has a cavity indentedtoward said front face.
 15. An iron type golf club head comprising: afront face having a grooved striking zone for impacting a golf ball; arear face opposite to said front face; a top portion; a sole portion; atoe portion; a heel portion; and a hosel portion having ashaft-receiving bore; wherein the toe portion surface meets said frontface along a first edge, and said toe portion extends outwardly fromsaid first edge in a direction away from said hosel portion such thatthe vertical projection of said toe portion onto a plane containing saidfront face is substantially located outside of said front face; whereinthe sole surface meets said rear face along a trailing edge and at leasta central portion of said trailing edge is indented toward said frontface.
 16. The iron type golf club head of claim 15, wherein the irontype golf club head has a moment of inertia about a vertical axisbetween 3000 grams-centimeters squared and 6000 grams-centimeterssquared, and said vertical axis passes through the center of gravity ofthe iron type golf club head and said vertical axis is perpendicular toa ground the iron type golf club head rests on.
 17. The iron type golfclub head of claim 15, wherein the distance AB between a point A, whichis the outmost point of said toe portion as viewed in a front view, anda point B, which is the outermost point of said first edge as viewed ina front view, is at least 4 mm.
 18. The iron type golf club head ofclaim 15, wherein when said sole rests on a ground, a distance ABbetween a point A, which is a vertical projection point on said groundof the outmost point of said toe portion as viewed in a front view, anda point B, which is a projection point on the ground of the central axisof said shaft-receiving bore, is substantially larger than a distance BCbetween said point B and a point C, which is a vertical projection pointon the ground of the outermost point of said first edge as viewed in afront view.
 19. The iron type golf club head of claim 15, wherein saidrear face has a cavity indented toward said front face.